He worked regularly in musical theater productions at Phoenix Little Theater during the 1970s and into the 80s. Then, at some point, he ended up moving to Italy, settling in Rome, where he taught English and appeared as an extra in several films. He also managed to land a few bigger and credited roles, but seems the only truly substantial role he played was as the deranger killer in Lucio Fulci's gory horror movie Un gatto nel cervello (1990).
At some point, he returned to the US, and passed away on 21st April 2016 in Phoenix, Arizona at the age of 84. He was survived by three sons and two granddaughters.
So far, I've only found two uncredited roles for David, but there are surely many more appearances to be found in Italian films and TV productions of the 1980s and 90s.
- Big Man: Polizza droga (TV) .... Hotel receptionst (credited as David Tompson)
- Arena .... Doctor (credited as Dave Thompson)
- Terminator 2 - Shocking Dark .... Henry Rafferson (uncredited)
- The Godfather Part III .... Party guest (uncredited)
- Un gatto nel cervello .... Professor Egon Schwarz (credited as David L. Thompson)
- Voyage of Terror: The Achille Lauro Affair (TV) .... American ambassador in Cairo (uncredited)
- Il principe del deserto (TV mini series) .... Holy man (credited)
- Miliardi .... Dr. Settani (credited)
- Boom - 3rd segment: "Il figlio di Maciste" .... Gordon Steel's friend on the sofa (uncredited)
- Errore fatale (TV movie, 1992)